Quick-change axial pin tumbler lock assembly



July 19, 1966 w. J. KERR QUICK-CHANGE AXIAL PIN TUMBLER LOCK ASSEMBLY'Filed July l5, 1964 I www) mail July 19, 1966 W. J, KERR 3,261,188

QUICK-CHANGE AXIAL PIN TUMBLER LOCK ASSEMBLY Filed July 15, 1964 5Sheets-Sheet 2 54 F165 n Q50 86 II@ 6 y '3| I8 |37 X/ |30 77 73 I4 42 ql'l' 52 INVENTOR: WILLIAM J. KERR ATT'Y July 19, 41966 w. J. KERR3,261,188

QUICK-CHANGE AXIAL PIN TUMBLER LOCK ASSEMBLY Fled July l5, 1964 3Sheets-Sheet 3 INVENTOR; WILLIAM J. KERR BY ATT'Y United States Patent O3,261,188 QUICK-CHANGE AXIAL PDI TUMBLER LOCK ASSEMBLY Wiiiiam I. Kerr,Glenview, Ill., assignor to Chicago Lock Company, Chicago, Ill., acorporation of Illinois Filed July 15, 1964, Ser. No. 382,914 11 Claims.(Cl. 70-363) The improved lock assembly comprising the present inventionhas been designed for use primar-ily in connec- -tion with the cabinetdoor of a vending machine where managerial policy dictates that the pintimbler combination of such vending machine lock assembly shall bechanged, or when proper occasion demands, frequently. The invention is,however, capable of other uses and lock assemblies constructed accordingto the present invention may find wide application in other elds toonumerous to mention.

The invention is concerned primarily with a lock assembly of Ithe axialpin tumbler type wherein the split pin-variety tumblers that areassociated therewith are circumferentially spaced about, and extendparallel to, the central longitudinal axis of the lock barrel, arespring pressed forwardly, and are designed for cooperation with a keyhaving rearwardly facing circumferentially spaced, tumbler-engagingshoulders which engage the forward ends of the split tumblers anddepress the tumblers upon proper insertion and manipulation of the keywith respect to the assembly. This -type of lock assembly is widely usedin connection with a vending machine which is installed in a publicplace such, for example, as a subway station or the like.

The changing in the iield of the pin tumbler combination of a lockassembly f the type and character under consideration has heretoforebeen hampered by the necessity of working from the rear or 4inner sideof the cabinet door and of dismantling as much of the ilock assembly asis necessary in order to render fthe split pin tumblers accessible forremoval and subsequent substitution or replacement. With an operatorworking from the back side of the cabinet door, the necessarily opencabinet door is frequently a hinderance to passers-by such as areencountered on a narrow subway platform. An additional limitationresides in the fact that the operator is burdened with the inconvenienceof taking charge of the various parts of the different lock assembliesthat are assigned to him 'for combination-changing purposes,

In my copending United States patent application Serial No. 336,795,filed on January 9, 1964, and entitled Quick-Change Axial PinTumb'lerLock Assembly, there is shown and described a lock assembly of the typeunder consideration and wherein pin tumbler change-over operations maybe performed in a relatively short period of time with most of the worktaking place from the front or outside of the cabinet door and with thedoor in its closed or nearly closed position. The present inventionrelates to a lock assembly which is of the same general type as thatforming the subject matter of such copending patent application, isstructurally similar thereto, but is so designed that pin tumblerchange-over operations may be effected wholly from the outside of thecabinet even, if necessary, without opening or even unlocking thecabinet door. The provision of such a lock assembly being the principaland general object of the invention, it is another object to providesuch a lock assembly which requires that the operator carry no specialtools or assembly parts whatsoever, other than a small latch-release pinand, of course, the necessary replacement key to iit the new pin tumblercombination after the change-over operation has-been completed.

Other objects and advantages of the invention, not at ICC this timeenumerated, will readily suggest themselves as the following descriptionensues.

In the accompanying three sheets of drawings forming a part of thisspecification, two illustrative embodiments of the invention have beenshown.

In these drawings:

FIG. 1 is a front perspective view of a lock assembly constructed inaccordance with the principles of the present invention, the operatingkey of the assembly being shown in its assembly-unlocking positionwithin the lock assembly;

FG. 2 is a rear perspective view of the improved lock assembly, theparts of the assembly being shown in their unlocked position;

FIG. 3 is an exploded front perspective view ofthe lock assembly withthe parts in their locked position;

FIG. 4 is a transverse sectional view taken substantially on thevertical plane indicated by the line 4--4 of FIG. l and in the directionindicated by the arrows;

FIG. 5 is a longitudinal sectional View taken substantially on the line5 5 of FIG. 4;

FIG. 6 is a transverse sectional view taken substantially on the line6-6 of FIG. 5;

FIG. 7 is an exploded perspective view of the lock assembly,illustrating the manner in which a pin tumbler change-over operation iseifected in s-itu with the aid of a latch-release pin;

FIG. 8 is a sectional view similar to FIG. 6 but showing the parts ofthe lock assembly in their locked posit1on;

FIG. 9 is a fragmentary side elevational view, partly in section, of aportion ofthe structure shown in FIG. 8 and illustrating specifically*theA position of the rotary latch member which forms a part of theimproved lock assembly;

FIG. 10 is a sectional view similar to FIG. 6 but showing the parts inan overrun posi-tion for cap removal purposes;

FIG. 1l is a fragmentary sectional view taken substantially on the line11-11 of FIG. 10;

FIG. l2 is a sectional view taken substantially along the line 12-12 ofFIG. 6;

FIG. 13 is a sectional view similar to FIG. 12 but showing the latchmember in its position of release under the influence of thelatch-release pin;

FIG. 14 is a perspective view of the latch-release member;

FIG. 15 is a sectional view similar to FIG. 9, showing a modified formof rotary latch member;

FIG. 16 is an exploded perspective view of the modied form of rotarylatch member illustrated in FIG. 15; and

FIG. 17 is a sectional view taken on the line 1717 of FIG. 15.

Referring now to the drawings in detail and in particular to FIGS. l to3, inclusive, wherein a preferred form of lock assembly embodying thequickchange features of the present invention has been illustrated anddesignated in its entirety by the reference numeral 10, the key foroperating the lock assembly is shown at 12. The lock assembly is of theaxial pin tumbler type, which is to say that the split pin tumblers thatare associated therewith and form a part thereof extend in the axialdirection of the lock barrel and are shiftable endwise upon engagementwith forwardly facing pin-actuating shoulders on the operating key 12.

Specifically, the lock assembly 10 is similar in many respects to thelock assembly which is shown and described in my aforementionedicopending patent application Serial No. 336,795, and it differstherefrom solely in the means whereby the front key-receiving cap isreleased so that it may be removed and the forward end portions of thesplit pin tumblers made accessible for tumbler interchange orreplacement pur-poses. Whereas, in the lock assembly of my copendingapplication, such release of the key-receiving lcap is effected with theaid of a suitable release pin which is inserted through a hole in thelock barrel at the rear of the cabinet door on which the lock assemblyis installed, release of the cap in the present instance ris effected byinsertion of a release pin through a hole in the ca-p itself, andconsequently, the release oper-ation may be effected from in front ofthe cabinet door, even without opening the door.

An understanding of the present invention will be facilitated by a briefpreliminary description of the common structures involved in connectionwith both lock assemblies -and by means of which release of thekey-retaining caps may be effected at will by .an operator for pintumbler change-over operations. As shown in FIG. 3 of the presentdrawings, a key-receiving cap Sil having ydiamet-rically opposite andrearwardly extending hook portions 86 is releasably held within acupashaped protective washer 30 which is adapted to be fixedly clampedagainst the front side of a cab-inet door, such as the door 26 ofFIG. 1. A rim flange 16 on the usual tubular lock barrel 14 is providedwith voids 122 which receive the hook portions 86 and hold the cap 80against rotation with respect to the lock barrel 14. The side walls ofthe voids 120 and the hook portions 86 constitute fixed interengagingmeans for preventing rotation of the cap relative to said lock barrel.In addition to the barrel, the lock assembly 10 is :provided with arotatably mounted lock shaft 42. The latter is provided with Ianenlarged head 70 which is rotatable within the lock barrel :and has -anannular rim flange 88 with a lpair of diametrically opposite notches120. The rim flange 88 slides behind the hook portions S6 of the cap 80and normally prevents removal of the cap from the washer 30. However,when the notches 120 register with-the hook portions 86, the cap may beremoved by pulling it forwards with respect to the washer 30 of the lockassembly. The cap 80 conceals the forward ends of an -annular series ofcircumferenti-ally spaced shaft pins 66 at the front portion of a splitpin tumbler arrangement and, when the cap is removed, these pins areaccessible for interchange or substitution. The shaft prins are bodilyrotatable with the lock shaft 42 and the latter may normally be turnedby means of the key 12 through an angle of 90 between door-locking anddoor-releasing positions. In neither of these two extreme positions dothe notches 120 move into register with the hook portions 86 of the cap80, and thus the cap is normally retained in position against removalfrom the cap 80. However, by release of a certain lat-ching mechanismthat is operable under the control of la latch-release pin 130 (see FIG.7), the lock shaft 42 may be turned through an additional angle of221/2o to bring the notches 120 and the hook portions 86 into registerfor cap-release purposes. The pin 130 is insertable through a small hole131 in the cap 80 `and through a longitudinal bore 133 in the stationarylock barrel 14 and it cooperates with a spring biased, collarlike latchmember 135 having a combined limit stop and latch pin 137 which normallyrides on a 90 sector 139 (see FIGS. 3, 6 and l0) between the locked andunlocked lpositions of the lock shaft 42, but which m-ay be pushedrearwardly by means of the latch-release pin 130 so as to clear anintervening shoulder 141 and permit the pin 137 to ride upon a 221/2sector 143 in order thus to bring the notches 120 and the hook portions86 into register. As shown in the drawings, the sector 139, the shoulder141 and the sector 143 are formed on the inner or rear end of the lockbarrel 14. Apart from this capreleasing feature, the flock assembly ofthe present invention remains substantially the same as the lockassembly of my aforesaid copending patent application, such an assemblyhaving been selected for illustration herein as an exemplary form oflock assembly that is Icap-able of modification to include thecap-releasing feature of the present invention. It is to be distinctlyunderstood, however, that other forms of lock assemblies of the axialpin tumbler 4type are adaptable to the present cap-releasing feature byappropriate modification thereof if necessary.

Referring again to FIGS. 1 to 3 in more detail, the fixed tubular lockbarrel 14 of the lock assembly 10 is provided with an integral,rearwardly extending shank portion 18 of the interrupted screw threadedtype, which is to say that the external threads 20 thereon areinterrupted by oppositely disposed flats 22 and 24 (see FIGS. 2 and 6).The lock assembly is shown in FIG. 1 as being operativelyinstalled uponthe swinging or hinged door 26 by means of a nut 28 which is threadedlyreceived on the threads 20 of the shank portion 18 and cooperates withthe previously mentioned protective washer 30 in clamping the doortherebetween. The tubular lock barrel 14 projects rearwardly through anopening 32 in the ldoor 26 as shown in FIG. 5.

The lock shaft is rotatably disposed in 4a longitudinal bore 40 (seeFIG. 5) in the lock barrel 14 and the rear end of the shaft projectsoutwardly of the barrel and is provided with a male or external screwthread 44. Flats 46 (see FIG. 2) on the threaded rear end of the lockshaft 42 :cooperate with a substantially rectangular hole 48 in theproximal end in a radial locking cam 50 in maintaining the camnon-rotative on the shaft. A nut 52 on the threaded rear en-d of thelock shaft 42 serves effectively to clamp the locking cam 50 in place.The locking cam 50 is designed for cooperation with the fusual lockingshoulder 54 (see FIG. 5) in maintaining the door 26 in its closedposition against the usual gasketed door opening jamb (not shown).

An annular series of circumferentially spaced, axially extending sockets60 are formed in the lock barrel 14 and receive slidable therein theusual non-rotatable barrel pins 64 at the rear portion of theaforementioned split pin tumbler arrangement. The cooperating shaft pins66 are slidable in axial bores 68 in the enlarged head 70 at the frontof the lock shaft 42, such bores being arranged in an annular series andspaced circumferentially. Helical compression springs 72 in the rearends of the sockets urge the pins 64 and 66 in a forward direction. Theforward ends of the bodily rotatable shaft pins 66 cooperate withshoulders 74 Ion the key 12 in the usual manner of an axial pin tumblerlock assembly so that when the split tumblers are so disposed that thesplits which exist between the labutting ends of the pins 64 and 66occupy the same traverse plane, the lock shaft 42 may be turned withinthe barrel 14, otherwise not.

A forwardly extending key or pilot post 71 on the front end of the lockshaft 42 cooperates with an axially extending socket 73 in the tubularpart of the key 12 in aligning the key on the lock shaft 42. Alongitudinally extending notch 75 in the post 71 cooperates with alongitudinal spline 77 on the interior of the tubular part of the key sothat torque may be transmitted from the key to the lock shaft for shaftturning purposes. As previously described, the lock shaft is capable ofbeing rot-ated by the key throughout an angle of between the unlockedcondition of the cam 50 as shown in broken lines in FIG. 3 and thelocked condition thereof as shown in full lines. The shaft 42 also iscapable of being turned an additional small angle to the overrun orterminal position wherein it is shown in dotted lines in FIG. 3 whenreleased by the latch member of the present invention in order torelease the cap 80 and thus expose the shaft pins 66 at the frontportion of the split pin tumbler arrangement for changeover operations,all in a manner that will be described presently.

The key-receiving cap 80 is formed with the usual inturned key-receivingrim 81 while the protective Washer 30 is formed with a forwardlyprojecting annular wall 8.2.

which establishes a shallow forwardly facing recess 84 for telescopicreception therein of the cap 80. The previously mentioned rearwardlyextending hook portions 86 on the cap 80 encompass and slidingly hookbehind the interrupted or notched rim flange 88 on the enlarged head 70of the lock shaft 42 and constitutes slidable interengaging means which,as previously pointed out, normally prevents removable of the cap 80.When change-over operations are instituted, the lock shaft 42 may beturned through a 221/2 angle beyond its fully locked position aspreviously described so that the hook portions 86 register with thenotches 120 and permit forward movement and consequent removal of the-cap S0, this additional 221/2 movement of the shaft being contingentupon release of the shaft by the latch member 135. The inturnedkeyreceiving rim 81 of the cap 80 has a central opening 92 which iscoaxial with the forwardly extending key post 71 at the front end of thelock shaft 42 and through which the tubular part of the key 12 isadapted to be projected for lock operating purposes. Notches 94 and 95in the rim flange 81 of the cap 80 cooperate with a radial, outwardlyextending lug 96 on the key to permit entry of the key into centralopening 92 in the cap of the lock assembly and removal thereof from theassembly in either the unlocked or locked position of the assembly.

In order to determine the three limiting positions of which the lockshaft 42 is capable of assuming, the previously mentioned collar-likelatch member 135 cooperates on two levels, so to speak, with the endface sectors 139 and 141 (see FIGS. 3 and 6) on the rear end face of thefixed lock barrel 14. As best seen in FIGS. 12, 13 and 14, this latchmember 135 is in the form of a two-piece assembly consisting of an`annular body 151 and a thin, flat, flexible ring 157. The body of thelatch member is of appreciable thickness and its forward side isrelieved on a small angular bias as at 153 to provide a clearance space155 to allow for lateral flexing movement of the ring 157. The latter isformed of spring steel or other suitable spring material. It is riveted`as at 159 to the forward side of the annular body 151 and has a portionoverlying the clearance space 155. A previously mentioned combined limitstop and latch pin 137 projects forwardly Ifrom the ring 157 and isbacked by a helical compression spring 163 which seats within a socket164 in the body 151. The two-piece assembly which comprises the latchmember 135 is received over the rear end of the lock shaft 42 with thecombined limit stop and latch pin 137 opposing the rear end face of thelock barrel 14 so that the pin may ride normally on the 90 sector 139.When thus riding upon the sector 139, the pin 137 is limited in itsmovements by the previously mentioned shoulder 141 and a shoulder 165(see FIGS. 2 and 6) on the rear end face of the lock barrel 14. the twoshoulders being circumferentially spaced and opposed. When the combinedlimit stop and latch pin 137 is in position against the shoulder 167 asshown in FIG. 6, the lock assembly is in its unlocked condition. Whenthe pin 137 is in position against the shoulder 141, the lock assemblyis in its locked condition and the pin 137 is in register with thelongitudinal bore 133 (see FIGS. 3 and 8) in the lock barrel 14 so thatwhen the latchreleasing pin 130 is inserted through the hole 131 in thecap and projected through the bore 133, the combined limit stop andlatch pin 137 will be lifted from its seating engagement on the sector139 and caused to clear the shoulder 141 so that the lock shaft 42 maybe turned an additional 22% and the pin 137 ca-used to seat upon thesector 143 where its movement is limited by a shoulder 167 (see FIGS. 2and 10). With the pin 137 against the shoulder 167, the locking cam 50will assume the dotted line position wherein it is shown in FIG. 3, thecabinet door remaining locked, but the notches 120 in the rim flange 88becoming aligned with the rearwardly extending hook portions 86 on thecap 80 so that the cap is then released for removal purposes andconsequent exposure of the shaft pins 66 for interchange orsubstitution.

When the cap is thus removed, the shaft pins 66 at the front portion `ofthe split pin tumbler 'arrangement are exposed for removal, interchangeor replacement, as desired. The change-over operation may be effected invarious ways. Usually the service man will carry a small magnetic toolby means of which he m-ay attract the various shaft pins 66 which areloosely disposed Within the bores 68, the tool being employed for bothshaft pin removal and replacement purposes. An interchange between anytwo Idifferent length shaft pins 66 will suffice to change thecombination of the lock assembly and such a procedure will obviate thenecessity of the service man carrying a supply of shaft pins and ofkeeping track of their effective lengths. After a desired change-overoperation has been completed, a new key such as the key shown at 12A inFIG. 7 will be required to operate the lock assembly 10, such key beingprovided with shoulders 74A which are machined or otherwise formed toaccommodate the new split pin tumbler arrangement.

After a given tumbler interchange, replacement or substitution has beenmade, the cap 80 will be replaced in the shallow, circular, forwardlyfacing recess 84 in the protective w-asher 30 and the rearwardlyextending hook portions 86 of the cap resultantly caused to enter thevoids 122. Thereafter, the new key 12A is inserted through thekey-receiving opening 92 and brought into proper cooperation with theshaft p-ins 66, whereupon turning of the key in a counterclockwisedirection as viewed in FIGS. l and 3 will cause the latch pin 137 toslide off of the 221/2 sector 143 (see FIGS. 3 and 10) and move onto thesector 139, thus causing the rim flange 88 to slide behind the hookportions 86 and otherwise restoring the lock assembly to normaloperation between its locked and unlocked conditions.

It is to be noted at this point the latch-release pin 130 is employedonly once during any given tumbler changeover operation, it beingemployed to release the combined limit stop and latch pin 137 from theshoulder 141 and allow the lock shaft 42 to be turned to its overrunposition. In turning the lock shaft back to its 90 range of movement,the pin 137 is free to slide over the shoulder 141 without the aid ofthe pin 130. It also is to be noted that the notch 95 (see FIGS. 1, 3and 7) is provided, in addition to the notch 94, in order that the key12 may be removed from the cap 80 at the time of removal of the latterfrom the protective washer 30, this being a convenience to the serviceman who can then reapply the cap 80 to the lock assembly with no thoughtbeing given as to the orientation of the key 12A. Additionally, sincethe key 12 must be removed from the cap 30 for key replacement purposes,it is considered advantageous to be able to remove the key at thecommencement of a change-over operation immediately after the lock shaft42 has been turned to its extreme overrun position. Although thecombined limit stop and latch pin 137 is intended to be manipulated bymeans of the latch-release pin from the outside of the cabinet door, itis possible to manipulate this pin from behind the cabinet door in theevent that the service man has misplaced his operating tool 130. Thecollar-like latch member occupies an exposed position on the rear end ofthe lock shaft 42 so that it is possible to insert a flat tool such asthe blade of a pocket knife into the clearance space 155 (see FIG. 12)and pry the llexible ring 157 rearwardly and thus withdraw the combinedIlimit stop and latch pin 137 from its position of circumferentialregister with the shoulder 141 and allow further turning movement of thelock shaft 42 to its overrun position.

Finally, it is to be noted that upon insertion of the latch-releasingpin 130 through the hole 131 in the cap Sti and the aligned bore 133 1nthe lock barrel 14 and depression of the pin 137 to the ful-lest extentof which it is capable of being depressed as shown in FIG, 13, the pin137 remains in circumferential register with the shoul- 7 der 167 (seealso FIG. 3) so that it is impossible to turn the lock shaft beyond itsoverrun 221/2 position.

In FIGS. 15, 16 and 17, there has been illustrated a modified form oflatch member 335 capable of being substituted bodily for the latchmember 135 and which, when thus substituted, will cooperate with thelatch-release pin 130 to release the lock shaft 42 so that it may beturned through a final '221/2 angle in the manner previously describedin connection with the latch member 135 for cap-releasing purposes. InFIG. 16, this modified form of latch member has been illustrated inexploded fashion and `in FIGS. 15 and 17, the latch member 335 is shownas being operatively installed in a lock assembly 210 which, otherwise,is identical with the lock assembly 10 of FIGS. 1 to 3, inclusive.Therefore, only those portions of the lock assembly 210 which are in theimmediate vicinity of the latch member 335 have been illustrated inFIGS. and 17 and, furthermore, in order to avoid needless repetition ofdescription, similar reference numerals but of a higher order have beenapplied to the corresponding parts as between the disclosures of FIGS. 9and 15.

The latch member 335 is in the form of a collar-like annular body 351which is received over the lock shaft 242 and the forward or front endface of which is formed with a socket 364 therein providing a seat for aspring 363. The spring 363 serves to bias a combined limit stop andlatch pin 337 against the rear end face of the lock barrel 214, and whenthe lock shaft 242 is in its lock-ing position, the latch pin 337 is inaxial register with a bore 333 provided in the barrel so that a tool,such as the tool 130 of FIG. 7, may be projected through the bore 333and into engagement with the latch member for shaft-releasing purposesto the end that the lock shaft may then be turned through an angle of221/2 for capremoval purposes as described in connection with the lockassembly 10.

At such time as the end of the tool 130 engages the latch pin 337, thelatch pin is forcibly moved to a retracted position within the socket364 against the yielding action of the spring 363. When thus retracted,it clears a shoulder similar to the shoulder 141 of FIG. 8 on the rearend face of the lock barrel 214 so that it may move into register with asector similar to the sector 143.

As shown in FIG. 17, the rear end face of the annular body 351 is formedwith a recess 361 therein which affords a clearance for a splitretaining ring 367, the latter seating within an interrupted recess 365formed in the lock shaft 242. By such an arrangement, the annular body351 is maintained on the lock shaft 242 with its front end face indirect `opposition to the rear end face of the lock barrel 214 forproper cooperation between the latch pin 337 and the two sectors of theadjacent end face of the lock barrel which correspond to the sectors 139and 141 of FIG. 8.

The invention is not to be limited to the exact arrangement of partsshown in the accompanying drawings or described in this specification`as various changes in the details of c-onstruction may be resorted towithout departing from the spirit or scope of the invention. Forexample, whereas the overrun sector 143 (FIG. 8) has been shown anddescribed herein as being of 221/2 angular extent, other small angularextents for such sector are contemplated, the particular extent notbeing critical. Similarly, although the interlock between thekey-receiving cap 80 and the lock shaft 42 comprises male hook portions86 on the cap and female notches 120 on the shaft, a reversal of suchmale and female interlocking means or parts may be resorted to. Thecircumferential disposition of the tool-receiving hole 131 in the cap isnot necessarily at an approximately ten oclock position on the frontface of the cap as shown in FIGS. 1, 3 and 7, inasmuch as this hole andits counterpart bore 133 in the lock barrel 14 may be disposed whereverconvenient and wherever its location does not interfere with adjoiningand moving parts of the lock assembly. Therefore, only insofar as theinvention has particularly been pointed out in the accompanying claimsis the same to be limited.

Having thus described the invention what I claim as new and desire tosecure by Letters Patent is:

l1. In an axial pin tumbler lock assembly, in combination, anopen-ended, non-rotatable tubular barrel having an axial bore andannular front and rear end faces, a lock shaft rotatable Within saidbore and having an enlarged head presenting a rear end face in rotativesliding contact with said front end face of the barrel, an axial splitpin tumbler arrangement including cooperating barrel and shaft pins,said shaft pins projecting forwardly of the head for cooperation with akey and being freely removable endwise from the shaft head for purposesof pin interchange, a forwardly and axially removable annular cappositioned forwardly of the barrel and encircling said shaft head, fixedinterengaging means on the cap and barrel preventing rotation of thecap, said shaft being rotatable from a rst angular unlocked position,through a second angular locked position, to a third overrun terminalposition, slidable interenga-ging means on the cap and shaft headnormally preventing removal of the cap, said slidable interengagingmeans permitting forward removal of the cap `when the lock shaft is inits terminal position, a collar-like latch member mounted on androtatable with the lock shaft rearwardly of the barrel and including anaxially shiftable latch pin yieldingly and slidingly bearing against therear end face of said barrel, first, second and third spaced shoulderson said rear end face of the barrel engagea-ble by the latch pin todetermine said first, second and terminal positions of the lock shaftrespectively, there being access openings in said cap and barrel inaxial alignment with said latch pin when the latter is in positionagainst said second shoulder to permit depression of the latch pin by asuitable pin-like tool and consequent withdrawal of the latch pin fromsaid second shoulder to allow the lock shaft to be moved to its terminalposition 2. In an axial pin tumbler lock assembly, in combination, anopen-ended, non-rotatable tubular barrel having an axial bore andannular front and rear end faces, a lock shaft rotatable within saidbore and having an enlarged head .presenting a rear end `face inrotative sliding contact with said front end face of the barrel, anaxial split pin tumbler arrangement including cooperating barrel landshaft pins, said shaft pins projecting forwardly of the head forcooperation with a key and being freely removable endwise from the shafthead for purposes of pin interchange, a forwardly land axially removableannular cap positioned forwardly of the barrel and encircling said shafthead, fixed interengaging means on the cap and barrel preventingrotation of the cap, said shaft being rotatable from a first angularunlocked position, through a second angular locked position, to a thirdoverrun terminal position, slidable interengaging means on the cap andshaft head normally preventing removal of the cap, said slidableinterengaging means permitting forward removal of the cap when the lockshaft is in its terminal position, a collar-like latch member mounted onand rotatable with the lock shaft rearwardly of the barrel and includingan axially shiftable latch pin slidingly and yieldingly bearing againstthe rear end face of said barrel, first and second circumferentiallyspaced and opposed shoulders on said rear end face of the barrelengageable by the latch lpin for establishing the unlocked and lockedpositons of the lock shaft respectively, a third shoulder on said rearend face circumferentially spaced from the second shoulder on the sidethereof remote from the iirst shoulder and engageable by the latch pinfor establishing said terminal position of the lock shaft, there beingsmall diameter access bores in sfaid cap and barrel in axial alignmentwith said latch pin when the latter is in position against said secondshoulder to permit depression of the latch pin by a pinlikelatch-releasing tool projected through -said access bores and consequentwithdrawal of the latch pin from said 9 second shoulder to allow thelock shaft to be moved to its terminal position.

3. In an axial pin tumbler lock assembly, in combination, an open-ended,non-rotatable tubular barrel having an axial bore and annular front landrear end faces, a lock shaft rotatable within said bore and `having anenlarged head presenting a rear end face in rotative sliding contactwith said front end face of the barrel, an axial split pin tumblerarrangement including cooperating barrel and shaft pins, said shaft pinsprojecting forwardly of the head for cooperation with a key and beingfreely removable endwise from the shaft head for purposes of pininterchange, a forwardly and axially removable annular cap positionedforwardly of the barrel and encircling said shaft head, fixedinterengaging means on the cap and barrel preventing rotation of thecap, said shaft being rotatable from a first angular unlocked position,through a second angular locked position, to a third overrun terminalposition, slidable interengaging means on the cap and shaft headnormally preventing removal of the cap, said slidable interengagingmelans permitting forward removal of the cap when the lock shaft is inits terminal position, a collar-like latch member mounted on androtatable with the lock shaft rearwardly of the barrel and including anaxially shiftable combined limit stop and latch pin yieldingly bearingagainst the rear end face of said barrel, rst and secondcircum-ferentially spaced and opposed shoulders on said rear end face ofthe barrel establishing therebetween an arcuate path of sliding movementfor the latch pin, said shoulders being engageable by the latch pin -forestablishing the unlocked and locked positions of the lock shaftrespectively, and a third shoulder on said rear end facecircumferentially spaced from the second shoulder on the side thereofremote from the irst shoulder and connected thereto by Ia raised arcuatepath of sliding movement for the latch pin, said third shoulder beingengageable by the latch pin for establishing the terminal positlon ofthe lock shaft.

4. lIn an axial pin tumbler lock assembly, in combination, anopen-ended, non-rotatable tubular barrel having an axial bore andannular front and rear end faces, a lock shaft rotatable within saidbore and having an enlarged head presenting a rear end face in rotativesliding contact with said front end face of the barrel, an axial splitpin tumbler arrangement including cooperating barrel and shaft pins,said shaft pins projecting forwardly of the head for cooperation with akey and being freely removable endwise from the shaft head for purposesof pin interchange, a forwardly and axially removable annular cappositioned forwardly of the barrel and encircling said shaft head, fixedinterengagi-ng means on the cap and barrel preventing rotation of thecap, said shaft being rotatable from the first angular unlockedposition, through a second angular locked position, to a third overrunterminal position, slidable interengaging means on the cap and shafthead normally preventing removal of the cap, said slidableintereng-aging means permitting forward removal of the cap when the lockshaft is in its terminal position, a collar-like latch member mounted onand rotatable with the lock shaft rearwardly of the barrel and includingan axially shiftable combined limit stop and latch pin yieldinglybearing against the rear end face of said barrel, first and secondcircumferentially spaced and opposed shoulders on said rear end face ofthe barrel establishing therebetween an arcuate path of sliding movementfor the latch pin, said shoulders being engageable by the latch pin forestablishing the unlocked and locked positions of the lock shaftrespectively, and a third shoulder on said rear end facecircumferentially spaced from the second shoulder on the side thereofremote from the rst shoulder and connected thereto by a raised arcuatepath of sliding movement for the latch pin, said third shoulder beingengageable by the latch pin for establishing the terminal position ofthe lock shaft,

there being a small diameter access bores in said cap and barrelrespectively and in axial alignment with said latch pin when the latteris in position against said second shoulder to permit depression of thelatch pin by a pin-like latch releasing tool projected through saidaccess bores and consequent withdrawal of the latch pin from said secondshoulder to allow the lock shaft to be moved to its terminal position.

`5. In an axial pin tumbler lock assembly, in combination, anopen-ended, non-rotatable tubular barrel having an axial bore andannular front and rear end faces, a lock shaft rotatable within saidbore and having an enlarged head presenting a rear end face in rotativesliding contact with said front end face of the barrel, an axial splitpin tumbler arrangement including cooperating barrel and shaft pins,said shaft pins projecting forwardly of the head for cooperation with akey and being freely removable endwise from the shaft head for purposesof pin interchange, a forwardly and axially removable annular cappositioned forwardly of the barrel and encircling said shaft head, fixedinte'rengaging means on the cap and barrel preventing rotation of thecap, said shaft being rotatable from a first angular unlocked position,through a second angular locked position, to a third overrun te-rminalposition, slidable interengaging means on the cap and shaft headnormally preventing removal of the cap, said slidable interengagingmeans permitting forward removal of the cap when the lock shaft is inits terminal position, a collar-like latch member mounted on androtatable with the lock shaft rearwardly of the barrel, said latchmember including a relatively thick washer-like body having a front endface opposing the rear end face of the barrel, a limited peripheralregion of said front end face of the body being relieved to provide aclearance space, a thin flexible ring of spring material sesured to saidfront end face of the body at a region diametrically opposed to saidlimited peripheral region and having a portion overlying said clearancespace, a combined limit stop and latch pin mounted on the overlyingportion of the ring and slidingly and yieldingly bearing against therear end face of said barrel, and first, second and third spacedshoulders on said rea-r end face enlgageable by the latch pin todetermine said first, second and terminal positions of the lock shaftrespectively.

h `6. In an axial pin tumbler lock assembly, in combination, anopen-ended, non-rotatable tubular barrel having an axial bore andannula-r front and rear end faces, a lock shaft rotatable within saidbore and having an enlarged head presenting a rear end face in rotativesliding contact with said front end face o-f the barrel, an axial splittumbler arrangement including cooperating barrel and 4shaft pins, saidshaft pins projecting forwardly of the head for cooperation with a keyand being freely removable endwise from the shaft head for purposes ofpin interchange, a forwardly and axially removable annula-r cappositioned forwardly of the barrel and e-ncircling said shaft head,fixed interengaging means on the cap and barrel preventing rotation o-fthe cap, said shaft being`rotatable from a first angular unlockedposition, through a second angular locked position, to a third overruntermi-nal position, slidable interengaging means on the cap and shafthead normally preventing removal of the cap, said slidable interengagingmeans permitting forward removal of the cap when the lock shaft is inits terminal position, a collar-like latch member mounted on androtatable with the lock shaft rearwardly of the barrel, said latchmember including a relatively thick washer-like body having a front endface opposing the rear end face of the barrel, a limited peripheralregion of said front end face of the body being relieved to provide aclearance space, a thin flexible ring of spring material secured to saidfront end face of the body at a region diametrically opposed to saidlimited peripheral region and having a portion overlying said clearancespace, a combined limit stop and latch pin mounted on the overlyingportion of the ring and slidingly and yieldingly bearing against therear end face of said barrel, and first, second and third spacedshoulders on said rea-r end face engageable by the latch pin todetermine said first, second and terminal positions of the lock shaftrespectively, there being small diameter access bores in said cap and`barrel respectively and in axial alignment with said latch pin when thelatter is in position against said second shoulder to permit depressionof said latch pin by a pinlike latch-'releasing tool projected throughsaid access bores, accompanied by flexing of the overlying portion ofthe ring into said clearance space, and consequent withdrawal of thelatch pin from said second shoulder to allo-w the lock shaft to be movedto its terminal position.

7. In an axial pin-tumble-r lock assembly, the combination set forth inclaim 6 and wherein said first and second shoulders on the rear end faceof the barrel define therebetween an arcuate path of sliding movementfor the latch pin in one radial plane, and wherein said second and thirdshoulders on the rear end face of the barrel define therebetween anarcuate path of sliding movement for the latch pin in a second radialplane reanwardly of said one radial plane.

8. In an axial pin-tumbler lock assembly, in combination, an open-ended,non-rotatable tubular barrel having an axial bore and annular lfront andrear end faces, a lock shaft rotatable within said bore `and having 'anenlarged head presenting a rear end face in rotative sliding contactwith said front end face, an axial split pin tumbler arrangementincluding cooperating barrel land shaft pins, said shaft pins projectingforwardly iat the head for cooperating with a key and being freelyremovable endwise from the shaft head for purposes of pin interchange, aforwardly and laxially lremovable annular cap positioned -forwardly ofthe barrel land encircling said shaft head, ixed interengaging means onthe cap and barrel preventing rotation of the cap, said shaft beingrotatable from a first angular unlocked position, through a secondangular locked position, to a third overrun terminal position, slidableinterengaging means on the cap and shaft head normally preventingremoval of the cap, said slidable interengaging means permitting forwardremoval of the cap when the lock shaft is in its terminal position, acollar-like latch member mounted on and rotatable with the lock shaftrearwardly of the barrel and having a front end face opposing the rearend face of the barrel, there being a socket in said front end face, acombined limit stop and latch pin slidable in said socket, spring meansdisposed within the socket and yieldingly urging said latch pin againstthe rear end face of said barrel, and first, second and third spacedshoulders on said rear end face engageable by the latch pin to determinesaid first, second and terminal positions of the lock shaftrespectively, there being small diameter raccess bores in cap and barrelrespectively and in axial alignment with said latch pin when the latteris in position against said second shoulder to permit depression of saidlatch pin by -a latch-releasing tool projected through said access boresand consequent withdrawal of the latch pin from said second shoulder toallow the lock shaft to be moved to its terminal position.

9. In an axial pin-tumbler lock assembly, the combination set forth inclaim 8, wherein said first and second shoulders on the rear end face ofthe b-arrel dene therebetween an arcuate path of sliding movement forthe latch pin in one radial plane,' and wherein said second and thirdshoulders on the rear end `face of the barrel define therebetween anarcuate path of sliding movement for the latch pin in .a second radialplane Irearwardly of said one radial plane.

10. In an axial pin-tumbler lock assembly, in cornbination, anopen-ended, non-rotatable tubular barrel having an axial bore and`annular front and rear end faces, a lock shaft rotatable within saidbore and having an enlarged head presenting a rear end face in rotativesliding contact with said front end face, an axial split pin tumblerarrangement including cooperating barrel and shaft pins, said shaft pinsprojecting forwardly of the head for cooperation with a key and beingfreely removable endwise from the shaft head for purposes of pininterchange, a forwardly .and axially removable annular cap positionedforwardly of the barrel and encircling said shaft head, iixedinterengaging means on the cap and barrel preventing rotation of thecap, said shaft being rotatable from a first angular unlocked position,through a second angular locked position, to a third overrun terminalposition, slidable interengaging means on the cap and shaft headnormally preventing removal of the cap, said slidable interengagingmeans permitting forward removal of the cap when the lock shaft is inits terminal position, a collar-like latch member mounted on androtatable with the lock shaft rearwardly of the barrel and having afront end face opposing the rear end face of the barrel, there being asocket in said Ifront end face, a combined limit stop and latch slidablein said socket, spring means disposed within the socket tand yieldinglyurging said latch pin against the rear end face of said barrel, andfirst, second and third spaced shoulders yon said rear end faceengageable by the latch pin to determine said first, second andtermin-a1 positions of the lock shaft respectively, there being smalldiameter access bores in cap and barrel respectively and in .axialalignment with said latch pin when the latter is in position againstsaid second shoulder to permit depression of said latch pin by alatch-releasing tool projected through said access bore and consequentWithdrawal of the latch pin from said` second shoulder to allow the lockshaft to lbe moved to its terminal position, the rear end face of saidlatch member being `formed with a recess therein, and a retaining memberdisposed within said recess and interlocking with said lock shaft forpreventing rearward shifting of the latch member on the lock shaft.

11. In an axial pin-tumbler lock assembly, the cornbination set forth inclaim 10, wherein said first and second shoulders on the rear end faceof the barrel dene therebetween an arcuate path of sliding movement forthe latch pin in one radial plane, and wherein said second and thirdshoulders on the rear end face of the barrel define therebetween anarcuate path of sliding movement for the latch pin in a second radialplane rearwardlyof said one radial plane.

References Cited by the Examiner UNITED STATES PATENTS 3,102,412 9/1964Christopher 70-363 EDWARD c. ALLEN, Primary Examiner.

P. TEITELBAUM, Assistant Examiner.

1. IN AN AXIAL PIN TUMBLER LOCK ASSEMBLY, IN COMBINATION, AN OPEN-ENDED,NON-ROTATABLE TUBULAR BARREL HAVING AN AXIAL BORE AND ANNULAR FRONT ANDREAR END FACES, A LOCK SHAFT ROTATABLE WITHIN SAID BORE AND HAVING ANENLARGED HEAD PRESENTING A REAR END FACE IN ROTATIVE SLIDING CONTACTWITH SAID FRONT END FACE OF THE BARREL, AN AXIAL SPLIT PIN TUMBLERARRANGEMENT INCLUDING COOPERATING BARREL AND SHAFT PINS, SAID SHAFT PINSPROJECTING FORWARDLY OF THE HEAD FOR COOPERATION WITH A KEY AND BEINGFREELY REMOVABLE ENDWISE FROM THE SHAFT HEAD FOR PURPOSED OF PININTERCHANGE, A FORWARDLY AND AXIALLY REMOVABLE ANNULAR CAP POSITIONEDFORWARDLY OF THE BARREL AND ENCIRCLING SAID SHAFT HEAD, FIXEDINTERENGAGING MEANS ON THE CAP AND BARREL PREVENTING ROTATION OF THECAP, SAID SHAFT BEING ROTATABLE FROM A FIRST ANGULAR UNLOCKED POSITION,THROUGH A SECOND ANGULAR LOCKED POSITION, TO A THIRD OVERRUN TERMINALPOSITION, SLIDABLE INTERENGAGING MEANS ON THE CAP AND SHAFT HEADNORMALLY PREVENTING REMOVAL OF THE CAP, SAID SLIDABLE INTERENGAGINGMEANS PERMITTING FORWARD REMOVAL OF THE CAP WHEN THE LOCK SHAFT IS INITS TERMINAL POSITION, A COLLAR-LIKE LATCH MEMBER MOUNTED ON ANDROTATABLE WITH THE LOCK SHAFT REARWARDLY OF THE BARREL AND INCLUDING ANAXIALLY SHIFTABLE LATCH PIN YIELDINGLY AND SLIDINGLY BEARING AGAINST THEREAR END FACE OF SAID BARREL, FIRST, SECOND AND THIRD SPACED SHOULDERSON SAID REAR END FACE OF THE BARREL ENGAGEABLE BY THE LATCH PIN TODETERMINE SAID FIRST, SECOND AND TERMINAL POSITIONS OF THE LOCK SHAFTRESPECTIVELY, THERE BEING ACCESS OPENINGS IN SAID CAP AND BARREL INAXIAL ALIGNMENT WITH SAID LATCH PIN WHEN THE LATTER IS IN POSITIONAGAINST SAID SECOND SHOULDER TO PERMIT DEPRESSION OF THE LATCH PIN BY ASUITABLE PIN-LIKE TOOL AND CONSEQUENT WITHDRAWAL OF THE LATCH PIN FROMSAID SECOND SHOULDER TO ALLOW THE LOCL SHAFT TO BE MOVED TO ITS TERMINALPOSITION.